Healthy soils are full of life. The article Life Under The Ground mentions some amazing facts about the soil:
• Soils are home to 1/4 of the Earth’s biodiversity.
• The weight of earthworms under our native forests is greater than all of the other animals living in the forest.
• One teaspoon of healthy soil has more living things than there are people living on the earth.
This activity involves observing soil animals – either outside in the real world or virtually, online.
Observing Visible Soil Creatures
access to outdoor area covered with leaf litter, wood chips, or other organic material
hand lenses (magnifying glasses)
digital microscope (optional)
Common New Zealand Earthworms PowerPoint
access to other websites listed within this activity
To observe actual soil creatures, head outside with a trowel and some empty ice-cream containers.
Choose a shady spot that has moist leaf litter or soil covered with organic matter like bark or wood chips.
Scoop up some of the leaf litter and place it in a container.
Scrape the leaf litter away from the surface and scoop up some of the soil and place in a second container.
Look through the containers with hand lenses, or digital microscopes to discover what is living at or below the soil surface.
Use online resources such as Soilbugs, or What is this bug? Or download the Earthworm ID Key to identify the creatures. The Building Science Concepts booklet has a very good soil and web identification section.
To observe virtual soil creatures, check out the Science Learning Hub’s Common New Zealand Earthworms PowerPoint and their earthworm videos, Soilbug’s image gallery, or Landcare Research’s slugs, snails and worms.
Return the leaf litter, soil and soil creatures to the outdoor location.
Observing Microscopic Soil Creatures
sandpit or container of sand
3 mesh bags (fruit and vegetables are often packed in these)
fruit or carrot peelings or similar vegetable scraps
access to websites listed in the activity
There are many weird and wonderful microbial creatures in the soil world – including vampyrellids – protozoa that drill perfectly round holes through their prey’s cell walls. Can you guess how the microorganism got it’s name? You can visit websites to learn more about soil bacteria, fungi, protozoa and nematodes.
A web search will show some amazing images of these microbes. That’s really the only way to see them without the aid of some very powerful microscopes. One way we can ‘see’ them though, is in action. Soil microbes are very important for breaking down wastes and recycling nutrients. This activity follows on from the Soil Microbe activity and can be done any time of the year.
Place equal amounts of vegetable peelings in each of the three mesh bags.
Place one bag outside in an out-of-the way place. It will be the control.
Bury the second bag in a sandpit, or container of sand.
Bury the third bag in the compost bin.
Leave the ‘tails’ of the bags out so you can find them easily.
Use gloves to check on the bags after a day or two and continue to observe them for a couple of weeks. Do you notice any differences in the rates of decomposition? Microbes are everywhere and provided there is enough warmth and moisture, the peelings will all begin to break down. (Remember to wash your hands afterwards.)
A good compost bin is full of soil bugs – and should do the job more efficiently. Is this what you found?